Table 3. Screening of Different Sources of Fluoride in the β-Azidation of 1a to 2a^a.

entry	catalyst	conv (%)b
1	TBAF	97
2	Amberlite IRA400F–	82
3	Amberlite IRA900F–	90
4	KF on alumina	88
5	TBAF on silica gel	95

^aReaction conditions: 1a (1 mmol), TMSN₃ (1.05), F-sources (5 mol %), CH₃CN:H₂O_Az.(5 M), 60 °C.

^bConversion determined by GC analysis. The remaining material is unreacted 1a.